On the 65816, if you say "JSR foo" from bank $12, but "foo" is an
address in bank 0, most assemblers will conclude that you're forming
a 16-bit argument with a 16-bit address and assemble happily. 64tass
halts with an error. Up until v1.55 or so, you could fake it out
by supplying a large offset.
This no longer works. The preferred way to say "no really I mean to
do this" is to append ",k" to the operand. We now do that as needed.
I didn't want to define a new ExpressionMode for 64tass just to
support an operand modifier that should probably never actually get
generated (you can't call across banks with JSR!), so this is
implemented with a quirk and an op flag.
64tass v1.56.2625 is now the default.
(issue #104)